The Four Different Types of Clinical Quality Measures

Clinical Quality Measures (CQMs) have been a significant part of my work for the past 3 years.  My first foray into the CQM space was with the popHealth project, which is a reference implementation of the CQM logic that a provider or EHR vendor could use or incorporate into a software project.  popHealth was entirely focused on a family of CQMs called "proportion-based".

While the "proportion-based" CQMs get the majority of the attention with the healthcare community, it was not until a year working on popHealth that I discovered that there are a total of four different types of CQMs that affect how the CQM logic is implemented and reported.

The four different classifications of CQM logic are:

Proportion

• This is the type of CQM that most individuals are familiar with when referring to the Meaningful Use program.  
• These types of CQMs are routinely referred to as the "Numerator/Denominator" CQMs.  I recently wrote about the exception and exclusion logic, but it is worth noting that those CQM reporting characteristics are only applied to proportion-based CQMs.
• Usually, the proportion-based CQMs are a positive measurement of quality, meaning that usually, the higher the value of the Numerator/Denominator proportion, the better you are doing as a healthcare provider
• Example: "What percentage of women over the age of 45 and under the age of 65, who have had an outpatient encounter in the past 2 years, have had a mammography screening?"

Continuous Variable

• These CQMs are usually applied in the hospital CQM domain.  
• These types of CQMs measure the average time 
• Example: "What is the average time for Emergency Department (ED) admission until either Discharge or Admission to Inpatient Hospitalization?"

Episode of Care 

• These CQMs assess each distinct ‘encounter’ between a patient and a provider, during a a measurement period.
• A single patient can contribute to numerous considerations of the CQM result if they had numerous encounters
• Examples: "Did the provider measure the patient’s blood pressure during a particular episode?" or "Were heart attack patients discharged with an Rx for Aspirin during a particular episode?"

Longitudinal

• These CQMs take into account complete patient record with focus on a ‘measurement period’
• Examples: "Have patients who turned 2 years old during the measurement period received all required vaccinations on schedule?" or "Have diabetic patients received 2 foot exams during the measurement period?"

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. © Rob McCready, 2013.